Systems for the manufacture of cement clinker from cement raw meal have a rotary kiln and, connected upstream thereof as viewed in the direction of material flow, a cyclone suspension heat exchanger with a calcinator. Many pipelines that convey hot media in a cement manufacturing plant are subject to thermal expansion. For instance the gas riser pipeline in the calcinator stage may convey a 850° C. suspension of rotary kiln off-gas, hot meal, fuel and possibly also clinker cooler off-gas as the tertiary air flows upwardly from below. Such thermally severely stressed pipelines must be lined with refractory material.
In order to compensate for thermal expansions of such thermally severely stressed pipelines, which are often in an approximately vertical position or suspended in tall building structures, it is known to build compensators into the pipelines. The compensator must be able to compensate, first, for the differing expansions of the sheet-steel jacket of the pipeline and the supporting building and, second, for the differing expansions of the sheet-steel jacket and the refractory lining of the pipeline. If the expansion compensator is inadequate, the supporting consoles or brackets of a pipeline in the upper region of the cyclone suspension heat exchanger building may no longer rest on the platform structure of the building, which can lead to uncontrollable and critical loadings of the building as well as the pipelines and connectors conveying the hot media.
One reason for the functioning failure of prior compensators is that in the course of time the fine-grained solid conveyed in the hot suspension, for example hot cement raw meal and/or other aggressive media, can move from the interior into the expansion gap of the refractory lining, which heretofore has been arranged in the plane of the metallic compensating corrugated pipe. From there the media can penetrate into the temperature-stable jointing material serving as an elastic seal, causing the jointing material, to harden and lose its elasticity. Heretofore such hot-gas pipelines in the region of the compensator from time to time, by inserting scaffolds into the pipeline in order that the compensator and in particular the expansion gap can be inspected and serviced from inside, which, entails a considerable expenditure for the costs of the scaffold as well as the labor. International application publication WO 89/03001 published Apr. 6, 1989 entitled Fabric Expansion Joints for Exhaust Systems for Gas Turbines, uses a composite fabric belt to interconnect duct sections which must be removed to access the joint packing.